ISX EGR 550 hard to Start when Hot

[alamow]

I drive a 2010 Western Star with an ISX EGR 550hp which is hard to start when hot. The engine has covered 2.3 mil Km but had the head overhauled 18 months ago and new cams last month. Oil and water temps are stable.

Our State fatigue management rules allow 17 hours work time every 24 hours provided we take a 20 minute break from driving every 5 hours. If I shut down the engine during the 20 minute break I can not start the engine again. The symptom is a flat battery yet the batteries and all starter cables have been replaced, 3 Delco starter motors and now on the 4th which is a Mitsubishi. Additional earths have been added to the chassis and engine block, starter solenoids changed.

Once the engine has cooled (1.5hrs) the engine spins over at normal speed and starts. The Mitsubishi starter motor is an improvement requiring 30 mins cool off time. I run an icepack/APU when the engine is not running to keep the cab cool and batteries charged.

Cold or warm start absolutely no problems.

The truck tows triples (265k lbs) in high ambient temperature 38-47 cels. Fuel burn 2.7mpg.

Lately I just run the engine on high idle but it would be nice to shut the thing down and have a break from the noise and vibrations.

Any suggestions?

[Rawze]

Does it turn over nicely and just will not fire off?, or does it have trouble turning over like a dead battery and it is really sluggish?., or does it just turn over a cylinder or so, then will not turn over any more at all until it sits, like the engine is stuck on one cylinder?.

Are you loosing any coolant?. Have you checked the rod/main bearings etc. since it has started doing this?. re-checked the overhead valve adjustments?

It could possibly be getting coolant into one of the cylinders making it hydra-lock a bit until it cools off. Have you tried relieving all pressure from the coolant system (in a safe manner so you don't get burned) just before shutting engine off?.

Also, has anyone done any coolant pressure tests to ensure EGR cooler is not leaky?

[Nilao]

You say the symptom is a flat battery which leads me to believe you hit the key and nothing happens or you just get a click. If so I'm fairly certain its the temperature limiting switch in the starter.

Mine does not have the temp switch so I've never experienced it but I know ppl who have. And in your application I can almost guarantee you that engine is making that starter very hot.



You should be able to bypass it.

[alamow]

Thanks for your responses. The engine turns over up to a quarter of a turn and then stops. Very sluggish but will not turn further than a quarter of a turn until the engine cools. Once cooled the engine spins freely and starts normally.

I added 3 liters of water for the first time last week as water was pushed out of the expansion tank overflow after travelling a 1000km. I'm not sure if the mechanics had over filled the expansion tank as I did not lose water again. I did ask but there are three mechanics and I haven't caught up with all of them yet.

I'm not sure if the following is relevant. On a long decline with the engine brake activated there is a lot of white smoke from the exhaust. I rarely add oil between services, at most 4 liters over 20,000km.

The overhead has been checked twice, once by Cummins.

[Brock]

I don't want to freak you out but it sounds to me like your head gasket is leaking and your engine is hydrolocking. My peterbilt is doing this right now, exact same thing but if I hold the key.... it will soon half a crank, pause for a second or 2 then continue cranking till it fires up.

https://youtu.be/ZXqNAK7oMok

Just look at them bubbles......

[Nilao]

Man that suck. I hear cat piston packs are not what they used to be.

[DLC]

Alamow, are you using an Imperial Gallon or a US Gallon?

Those are crazy temperatures and crazy loads you guys pull down under.

Maybe see if you can get some reflective insulation to put between starter and the block?
12V fan to blow on starter possibly.

Good luck.

[Signature620]

If you're interested and have the tooling. Turn the engine with a 3/4" drive ratchet while it's in this 'hard to start' state. Then you should be able to tell if you have a mechanical issue or an electrical one. Also note any white smoke at cold starts.

[alamow]

Watched the video, Not a pretty sight. The company I work with has replaced two CAT Heads so far this year.

I will try removing the radiator cap before shut down and see if the engine starts.